Has anyone made any progress on this? I applied the changes listed in this discussion as well as modified the deletion functions so that they could still find the entries to be removed when you update or delete a session.

However, I am also getting the double global entries. My understanding is that the code:

Creates a calendar user entry for the teacher.

Creates a calendar site entry for the session.

I am still trying to figure out what the third entry might be for. What I do know is that, while it lists the custom field labels, it doesn't actually put the information in it in one of the three entries.

I would really like to get this thing working. I tried Booking module plugin however this one just seems a little more intuitive and Booking doesn't seem to work any better with the Site calendar.